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Bu C, Zhang C, Li Z, Gao L, Xie Z, Cai G. Autoantibodies to plasminogen and tissue plasminogen activator in women with recurrent pregnancy loss. Clin Exp Immunol 2007; 149:31-9. [PMID: 17425656 PMCID: PMC1942027 DOI: 10.1111/j.1365-2249.2007.03382.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Reduced fibrinolytic activity has been described in primary anti-phospholipid syndrome (PAPS), and may be responsible for thrombotic events. Antibodies to tissue type plasminogen activator (t-PA) or plasminogen (PLG) might contribute to the hypofibrinolytic state in autoimmune diseases, but the clinical significance of these antibodies is still unclear in recurrent pregnancy loss (RPL). The aim of this study is to evaluate the prevalence and clinical significance of anti-PLG and anti-t-PA antibodies in 87 patients with a history of RPL: 54 women with well-defined PAPS (mean age 32.5 years; range 26-38) and 33 women with unexplained RPL (mean age 30 years; range 24-39). IgG anti-PLG antibodies were found in 20 and four patients from the group with RPL/PAPS and unexplained RPL, respectively; IgG anti-t-PA antibodies were found in 11 and two patients from the above two groups, respectively. IgG anti-PLG antibodies were associated with the high risk of RPL (OR 7.2, P = 0.004), especially with RPL/PAPS (OR 11.2, P < 0.001) evaluated by Fisher's exact test, while IgG anti-t-PA were associated with RPL/PAPS (OR 10.0, P = 0.01) but not with RPL (OR 6.8, P = 0.06). A significant inhibition of exogenous fibrinolysis was observed by IgG fractions from patients with anti-PLG or anti-t-PA antibodies on microplates and on the human umbilical vein endothelial cells, compared with those from healthy controls. The prevalence of IgG anti-PLG antibodies was high in RPL patients, especially in RPL/PAPS, while the prevalence of IgG anti-t-PA antibodies was high in RPL/PAPS but not in RPL, and some of them might inhibit fibrinolysis in patients.
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202
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Bikle D, Teichert A, Hawker N, Xie Z, Oda Y. Sequential regulation of keratinocyte differentiation by 1,25(OH)2D3, VDR, and its coregulators. J Steroid Biochem Mol Biol 2007; 103:396-404. [PMID: 17229570 DOI: 10.1016/j.jsbmb.2006.12.063] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2006] [Indexed: 10/23/2022]
Abstract
Keratinocyte differentiation requires the sequential regulation of gene expression. We have explored the role of 1,25(OH)(2)D(3) and its receptor (VDR) in this process. VDR sequentially binds to coactivator complexes such as Vitamin D receptor interacting protein (DRIP) and steroid receptor coactivator (SRC) during differentiation. Different genes respond differently to the VDR/coactivator complexes as determined by knockdown studies. The binding of DRIP205 and SRC to VDR is ligand (i.e. 1,25(OH)(2)D(3)) dependent. LXXLL motifs in these coactivators are critical for this binding; however, the affinity for VDR of the different LXXLL motifs in these coactivators varies. Hairless is an inhibitor of 1,25(OH)(2)D(3) dependent gene transcription. A phiXXphiphi motif in hairless is crucial for hairless binding to VDR, and its binding is ligand independent. 1,25(OH)(2)D(3) displaces hairless and recruits the coactivators to VDREs. Hsp90 and p23 are chaperone proteins recruited to the DRIP/VDR complex, where they block the binding of the complex to VDREs and block 1,25(OH)(2)D(3) stimulated transcription. Thus four mechanisms explain the ability of 1,25(OH)(2)D(3) to sequentially regulate gene transcription during differentiation: changes in coregulator levels, their differential binding to VDR, differential gene responsiveness to the VDR/coregulator complexes, and chaperone proteins facilitating the cycling of VDR/coregulator complexes on and off the VDREs.
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203
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Li Z, Liu S, Xie Z, Mou Y. Based on wavelet transform to analyze rabbit somatosensory evoked potential. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2005:2668-71. [PMID: 17282788 DOI: 10.1109/iembs.2005.1617019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Rabbits were narcotized and stimulated by 0.5Hz electric pulse. Potential of scalp was sampled at 3764Hz. Wave components of rabbit somatosensory evoked potential (SEP) can be located precisely through the method of continuous wavelet transform (CWT). Frequency feature of SEP can also be analyzed by CWT. The technique of continuous wavelet transform, which can project a one-dimension signal into a two-dimension time-frequency space, will become a useful method to process medical electronic signal. Key words: wavelet transform, somatosensory evoked potential, single-trial.
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204
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Wang Z, Xie Z, Xie DM, Zhong X, Liu Y, Li H. The new magnitude coherence functions and their properties sensitive to phase. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2005:4727-30. [PMID: 17281297 DOI: 10.1109/iembs.2005.1615527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Because magnitude-squared coherence function (MSCFs) could lose some phase information, based on the core theorem for the frequency domain coherence in signal processing, called as double spectral theorem, we present the two types of new magnitude coherence functions (MCFs) in order to extract the coherence between two signals and give the conditions that they are equal to 0 or +1 or -1. Here, we further study their properties sensitive to initial phases of two signals and phase difference between two signals. Studying demonstrated that the two type MCFs not only reflect frequency domain coherence of two signals, but also reflect the phase relationship between two signals. One is sensitive to the phase difference between two signals and the other is either sensitive to the initial phases or the phase difference between two signals. We call the properties as their properties sensitive to phase.
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205
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Ma H, Niu Y, Wang Z, Li Z, Hua M, Xie Z. Association of the spectral features of heart period signal with SNP of NOS in the Chinese Han nationality population. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2005:2463-6. [PMID: 17282736 DOI: 10.1109/iembs.2005.1616967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
To explore association of the spectral features of heart period signal with SNPs at 5 sites of NOS gene in the subjects (male89, female77, aged 62.40+/-2.5 yrs) by allele specific primer PCR technique. It was found that the TT allelic genotype of NOS2 C-1173T associated with the highest RPH and TT allelic genotype of NOS3 G894T associated with the highest APH in HPS spectral parameters. This suggests the SNPs of NOS2 C-1173T and NOS3 G894T may be the deep layer factors to result in the variability of HPS spectral parameters.
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206
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Xie Z, Zhong X, Xie DM, Ma H, Liu Y, Li H, Wang ZF. The new magnitude-squared coherence functions and their properties sensitive to phase. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2005:4697-700. [PMID: 17281289 DOI: 10.1109/iembs.2005.1615519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Based on the core theorem of the frequency domain coherence in signal processing, called as double spectral theorem, we presented the two types of new magnitude-squared coherence function (MSCFs) in order to extract the coherence between two signals and gave the conditions that they are equal to 1 or 0. Here, we further studied their properties sensitive to initial phases of two signals and phase difference between two signals. Studying demonstrated that the two type MSCFs not only reflect frequency domain coherence of two signals, but also reflect phase relationship between two signals. One is sensitive to the phase difference between two signals and the other is either sensitive to the initial phases or phase difference between two signals. We call the properties as their properties sensitive to phase.
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207
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Liu Y, Xie Z, Xie DM, Zhong X, Wang Z, Li H. Double Spectral theorem and Two Type Magnitude Coherence Functions. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2005:4723-6. [PMID: 17281296 DOI: 10.1109/iembs.2005.1615526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Studying frequency domain representation for the coherence between two signals is an important basic theoretical problem in the fundamental theories of signal processing. However, magnitude-squared coherence function (MSCFs) could lose some phase information. Based on the core theorem in the frequency domain coherence theories, called as double spectral theorem (DST), we presented the two types of new magnitude coherence functions (MCFs), called as the same type magnitude coherence function (SMCF) and the difference magnitude coherence function (DMCF) respectively, which had been mathematically derived from DST and the conditions that they are equal to 1 or -1 or 0 were theoretically derived from DST. Here, we further demonstrated that SMCF and DMCF could be used to exactly extract the coherence between two signals by each component.
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208
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Ebinghaus R, Xie Z. Occurrence and air/sea-exchange of novel organic pollutants in the marine environment. ACTA ACUST UNITED AC 2007. [DOI: 10.1051/jp4:2006139016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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209
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Chan K, Jones W, Xie Z, Cheng H, Liu Z, Covey J, Ludwig J, Szakacs G, Gottesman M. 192 POSTER Oral bioavailability and pharmacokinetics in CD2f1 mice of NSC73306, an antitumor agent that selectively kills multidrug-resistant cancer cells. EJC Suppl 2006. [DOI: 10.1016/s1359-6349(06)70197-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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210
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Chan K, Chen P, Xie Z, Kulp S, Chen C, Covey J. 602 POSTER Pharmacokinetics of Akt inhibitor NSC 728209 in the rat by LC/MS/MS method. EJC Suppl 2006. [DOI: 10.1016/s1359-6349(06)70607-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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211
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Xie Z, Kulasiri D. Modelling of circadian rhythms in Drosophila incorporating the interlocked PER/TIM and VRI/PDP1 feedback loops. J Theor Biol 2006; 245:290-304. [PMID: 17157878 DOI: 10.1016/j.jtbi.2006.10.028] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2006] [Revised: 10/24/2006] [Accepted: 10/26/2006] [Indexed: 10/23/2022]
Abstract
Circadian rhythms of gene activity, metabolism, physiology and behaviour are observed in all the eukaryotes and some prokaryotes. In this study, we present a model to represent the transcriptional regulatory network essential for the circadian rhythmicity in Drosophila. The model incorporates the transcriptional feedback loops revealed so far in the network of the circadian clock (PER/TIM and VRI/PDP1 loops). Conventional Hill functions are not assumed to describe the regulation of genes, instead of the explicit reactions of binding and unbinding processes of transcription factors to promoters are modelled. The model simulates sustained circadian oscillations in mRNA and protein concentrations in constant darkness in agreement with experimental observations. It also simulates entrainment by light-dark cycles, disappearance of the rhythmicity in constant light and the shape of phase response curves resembling that of the experimental results. The model is robust over a wide range of parameter variations. In addition, the simulated E-box mutation, per(S) and per(L) mutants are similar to that observed in the experiments. The deficiency between the simulated mRNA levels and experimental observations in per(01), tim(01) and clk(Jrk) mutants suggests some difference on the part of the model from reality.
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212
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Chen Y, Yang C, Xie Z, Zou L, Ruan Z, Zhang X, Tang Y, Fei L, Jia Z, Wu Y. Expression of the novel co-stimulatory molecule B7-H4 by renal tubular epithelial cells. Kidney Int 2006; 70:2092-9. [PMID: 17051145 DOI: 10.1038/sj.ki.5001867] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Crosstalk between T cells and renal tubular epithelial cells (TECs) in the pathogenesis of tubular lesions, the most important sign of progressive renal diseases, has not been clarified. Previous work has shown that TECs harbor co-stimulatory signals that promote T-cell activation, which induces tubular lesions. Nevertheless, the expression and functional role of B7-H4, a recently identified co-stimulatory ligand of the B7 superfamily, in pathologic human kidneys is unclear. We investigated the expression of B7-H4 on cryostat renal biopsies from patients with idiopathic membranous nephropathy (n=20), immunoglobulin A nephropathy (n=19), lupus nephritis (n=16), and acute renal allograft rejection (n=15) using immunohistochemistry. In addition, we also analyzed TEC-associated B7-H4 in the regulation of T-cell activation. Immunohistological staining revealed that B7-H4 antigen is restricted to tubular epithelium and that the protein is prominent in sections with severe tubular lesions, although no correlation was observed between tubular B7-H4 expression and levels of serum creatinine, serum urea nitrogen concentration, and 24-h proteinuria in each type of nephropathy. In vitro, mixed lymphocyte reactions revealed that TEC-related B7-H4 promotes cytokine (interleukin-2 and interferon-gamma) production and proliferation of co-cultured T cells. Interestingly, the secretion of interleukin-2 by C10 T cell hybridomas also increased when C10 cells were co-cultured with the B7-H4-transgenic murine TEC line, 3M-1-secreting tubular epithelial cells (MCT) in the presence of the antigen hen egg lysozyme. Our results clearly show that TEC-associated B7-H4 induces T-cell activation and we propose that B7-H4 is a potential activator that promotes tubular lesion.
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213
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Chen GL, Novak MA, Hakim S, Xie Z, Miller GM. Tryptophan hydroxylase-2 gene polymorphisms in rhesus monkeys: association with hypothalamic-pituitary-adrenal axis function and in vitro gene expression. Mol Psychiatry 2006; 11:914-28. [PMID: 16847459 DOI: 10.1038/sj.mp.4001870] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Tryptophan hydroxylase-2 (TPH2) is a newly identified second form of TPH responsible for serotonin synthesis in the brain and has been increasingly implicated as a contributor to the etiology of various psychiatric disorders. In this study, we have identified the constellation of polymorphisms in rhesus monkey TPH2 and investigated genotype/phenotype association as well as gene expression effects of specific polymorphisms. Genomic DNA was obtained from 247 rhesus monkeys, among which 24 had been previously examined for plasma cortisol level, dexamethasone suppression, and combined dexmethasone/ACTH challenge. Polymorphisms in all exons, splicing junctions and approximately 2 kb of the 5'-flanking region (5'-FR) of TPH2 were identified by sequencing. We identified 17 single nucleotide polymorphisms (SNPs) including two that are predictive of amino-acid change (25Pro>His and 75Gly>Ser, respectively), two mononucleotide repeats, one dinucleotide repeat, and one 159-bp insertion polymorphism. The 3'-UTR polymorphisms were significantly associated with hypothalamic-pituitary-adrenal (HPA) axis activity, especially 2051A>C, which was strikingly correlated with plasma cortisol level in the morning only (F=10.203, P=0.001). Luciferase reporter gene assays showed that the 3'-UTR polymorphisms and haplotypes had a profound effect on in vitro gene expression. Accordingly, these investigations revealed that polymorphisms in 3'-UTR of rhesus monkey TPH2 modulate HPA axis function, presumably by affecting levels of TPH2 expression.
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214
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Xie Z, Herring BE, Fox AP. Excitatory and inhibitory actions of isoflurane in bovine chromaffin cells. J Neurophysiol 2006; 96:3042-50. [PMID: 16956992 DOI: 10.1152/jn.00571.2006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Isoflurane, a halogenated volatile anesthetic, is thought to produce anesthesia by depressing CNS function. Many anesthetics, including isoflurane, are thought to modulate and/or directly activate GABA(A) receptors. Chromaffin cells are known to express functional GABA(A) receptors. We previously showed that activation of the GABA(A) receptors, with specific agonists, leads to cellular excitation resulting from the depolarized anion equilibrium potential. In this study, our goal was to determine whether isoflurane mimicked this response and to explore the functional consequences of this activation. Furthermore, we sought to study the actions of isoflurane on nicotinic acetylcholine receptors (nAChRs) as they mediate the "sympathetic drive" in these cells. For these studies the Ca(2+)-indicator dye fura-2 was used to assay [Ca(2+)](i). Amperometric measurements were used to assay catecholamine release. We show that bovine adrenal chromaffin cells were excited by isoflurane at clinically relevant concentrations. Isoflurane directly activated GABA(A) receptors found in chromaffin cells, which depolarized the cells and elevated [Ca(2+)](i). Application of isoflurane directly to the chromaffin cells elicited catecholamine secretion from these cells. At the same time, isoflurane suppressed activation of nAChRs, which presumably blocks "sympathetic drive" to the chromaffin cells. These latter results may help explain why isoflurane produces the hypotension observed clinically.
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215
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Zhou J, Pan M, Loh S, Xie Z, Lim Y, Lilly M, Glaser K, Albert D, Davidsen S, Chen CS. ABT-869, a novel multi-target receptor tyrosine kinase inhibitor (RTKI), combined with chemotherapy is synergistic in the therapy of acute myeloid leukemia cells with FLT3-ITD mutation (FLT3-AML). J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.13064] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
13064 Background: Internal tandem duplications (ITDs) of fms-like tyrosine kinase 3 (FLT3) receptor are identified in 20–25% of adult AML patients associated with poor prognosis. ABT-869 is active in FLT3-AML and is currently under clinical investigaton. We hypothesize that the combination of ABT-869 with chemotherapy can improve the therapeutic index in FLT3-AML. Methods: Using Calcusyn software, the additive, synergistic or antagonistic effect of ABT-869 with concurrent or sequential cytosine arabinoside (Ara-C) or doxorubicin (Dox) was measured in MV4–11 and MOLM-14 cells. The synergistic combination sequence was further tested in a MV4–11 xenograft model in four groups (10 mice/group) including control, Ara-C, ABT-869, and combination (Ara-C first for 4 days, then daily ABT-869). Cell cycle analysis and apoptosis and signal pathway assays were performed in vitro and in vivo. Results: ABT-869 induced dose- and time-dependent apoptosis on FLT3-AML cells resulting in down regulation of p-FLT3, p-STAT5, Bcl-XL and up regulation of p53 and BID. ABT-869 caused G1-phase arrest and the removal of cells in the S- and G2/M-phase mediated by reduction of cyclins D and E. We observed significant synergistic effect with Ara-C or Dox first, followed by ABT-869, as well as in concurrent treatment with ABT-869 and Dox. Simultaneous treatment with ABT-869 and Ara-C only achieved additive effect. Conversely, we found an antagonistic effect in the sequence of pretreatment of ABT-869 followed by chemotherapy. In a MV4–11 xenograft model, all mice succumbed to leukemia in the control and Ara-C groups (median survival = 53 and 55.5 days respectively). Combination therapy gave a faster reduction of tumor volume compared to ABT-869 treatment alone (p=0.03) without recurrence of leukemia in either group by day 67. In vivo immunohistochemistry (IHC) analysis revealed ABT-869 potently inhibited VEGF and phosphor-ERK. Conclusions: ABT-869 can be given after Ara-C or Dox to act synergistically. Our study suggests that combinations of RTKIs with chemotherapy should be carefully tested prior to clinical protocol development. A clinical trial of such combination therapy in FLT3-AML is warranted. No significant financial relationships to disclose.
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216
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Kennedy DJ, Vetteth S, Periyasamy SM, Kanj M, Fedorova L, Khouri S, Kahaleh MB, Xie Z, Malhotra D, Kolodkin NI, Lakatta EG, Fedorova OV, Bagrov AY, Shapiro JI. Uremic Cardiomyopathy—An Endogenous Digitalis Intoxication? J Am Soc Nephrol 2006. [DOI: 10.1681/asn.2006040389] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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217
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Xie Z, Adamowicz WO, Eldred WD, Jakowski AB, Kleiman RJ, Morton DG, Stephenson DT, Strick CA, Williams RD, Menniti FS. Cellular and subcellular localization of PDE10A, a striatum-enriched phosphodiesterase. Neuroscience 2006; 139:597-607. [PMID: 16483723 PMCID: PMC1464838 DOI: 10.1016/j.neuroscience.2005.12.042] [Citation(s) in RCA: 156] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2005] [Revised: 11/17/2005] [Accepted: 12/15/2005] [Indexed: 11/16/2022]
Abstract
PDE10A is a recently identified phosphodiesterase that is highly expressed by the GABAergic medium spiny projection neurons of the mammalian striatum. Inhibition of PDE10A results in striatal activation and behavioral suppression, suggesting that PDE10A inhibitors represent a novel class of antipsychotic agents. In the present studies we further elucidate the localization of this enzyme in striatum of rat and cynomolgus monkey. We find by confocal microscopy that PDE10A-like immunoreactivity is excluded from each class of striatal interneuron. Thus, the enzyme is restricted to the medium spiny neurons. Subcellular fractionation indicates that PDE10A is primarily membrane bound. The protein is present in the synaptosomal fraction but is separated from the postsynaptic density upon solubilization with 0.4% Triton X-100. Immuno-electron microscopy of striatum confirms that PDE10A is most often associated with membranes in dendrites and spines. Immuno-gold particles are observed on the edge of the postsynaptic density but not within this structure. Our studies indicate that PDE10A is associated with post-synaptic membranes of the medium spiny neurons, suggesting that the specialized compartmentation of PDE10A enables the regulation of intracellular signaling from glutamatergic and dopaminergic inputs to these neurons.
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218
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Ma QM, Liu Y, Xie Z, Wang J. Ab initio Study of Geometries and Magnetic Properties of Small Co Clusters. ACTA ACUST UNITED AC 2006. [DOI: 10.1088/1742-6596/29/1/031] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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219
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Davies BJ, Xie Z, Zou MH. 172 ACTIVATION OF THE ADENOSINE MONOPHOSPHATE-ACTIVATED KINASE BY THE ANTIDIABETES DRUG METFORMIN IMPROVES NITRIC OXIDE BIOACTIVITY IN VIVO. J Investig Med 2006. [DOI: 10.2310/6650.2005.x0008.171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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220
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Xie Z, Davis B, Zhang M, Zou MH. 1 REGULATION OF LKB1-DEPENDENT ADENOSINE MONOPHOSPHATE-ACTIVATED PROTEIN KINASE BY PROTEIN KINASE C-z R. J Investig Med 2006. [DOI: 10.2310/6650.2005.x0008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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221
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Anderson C, Miyagi T, Xie Z, Reddi H, Odero-Marah V, Johnstone P, Crocker I, Chung L. Probing Radiation Effects on Prostate Cancer and Bone Stroma Interactions. Int J Radiat Oncol Biol Phys 2005. [DOI: 10.1016/j.ijrobp.2005.07.204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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222
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Hsieh CL, Xie Z, Liu ZY, Green JE, Martin WD, Datta MW, Yeung F, Pan D, Chung LWK. A luciferase transgenic mouse model: visualization of prostate development and its androgen responsiveness in live animals. J Mol Endocrinol 2005; 35:293-304. [PMID: 16216910 DOI: 10.1677/jme.1.01722] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Numerous mouse models of prostate carcinogenesis have been developed, but hitherto there has been no model in which the prostate gland could be imaged in live animals. The transgenic model generated here targeted mouse prostate gland using a firefly luciferase enzyme under the control of a small but highly active and specific supra prostate-specific antigen (sPSA) promoter. We evaluated postnatal prostate development, involution and androgen-induced restoration of prostate growth in adult transgenic mice using bioluminescence imaging. Results of our study showed that: (i) the prostate gland of male offspring did not yield a significant bioluminescence signal until after sexual maturity. Luciferase was detected in the luminal epithelial cells of the ventral and dorsolateral lobes of the prostate gland and caput epididymis, with little or no activity in 18 other organs evaluated. (ii) While a constant high level of bioluminescence was detected in the mouse prostate from 5 to 35 weeks of age, a slight drop in bioluminescence was detected at 36 to 54 weeks. (iii) Upon castration, the luciferase activity signal associated with mouse prostate detected by a cooled charge-coupled device camera was dramatically reduced. This signal could be rapidly restored to pre-castration levels after androgen administration. Androgen-induced luciferase activity subsided to nearly basal levels 5 days following the last injection. These data demonstrate that a bioluminescent mouse model with luciferase activity restricted to the prostate gland under the control of a (sPSA) promoter can be used on a real-time basis in live animals to investigate the development and responsiveness of the prostate gland to exogenously administered androgen. This model can be extended to detect the responsiveness of the prostate gland to therapy and used as a founder strain to visualize tumors in hosts with different genetic backgrounds.
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223
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Zhong G, Wang J, Xu M, Xie Z, Yu M, Wang J, Zhou T, Gong W, Sun Y, Hu M, Zhang X, Shen B, Guo N. Enhanced Maturation and Functional Capacity of Dendritic Cells Induced by Mannosylated L2 Domain of ErbB2 Receptor. Scand J Immunol 2005; 62:108-16. [PMID: 16101816 DOI: 10.1111/j.1365-3083.2005.01642.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The nature of antigens and functional state of dendritic cells (DC) are important in antigen presentation. The ability of DC for the induction of T-cell responses is promoted by maturation. It has been confirmed that mannose receptors mediate highly efficient endocytosis and presentation of mannosylated proteins. In the present study, L2 domain of ErbB2 ectodomain was expressed in Escherichia coli, purified and mannosylated. The maturation and functional capacity of DC induced by mannosylated L2 (mL2) protein were investigated. The results showed that L2 protein could induce DC maturation, which was accompanied by elevated expression of MHC and co-stimulatory molecules. The effect of mL2 protein on DC maturation was more remarkable than that of non-mL2 proteins. Uptake of mL2 antigens by DC was more efficient. Furthermore, the T cells can be stimulated to proliferate in vitro and secrete Th1 and Th2 cytokines. Higher levels of both IFN-gamma and IL-10 were detected from the T cells stimulated by mL2-pulsed DC, suggesting a concurrent activation of CD4+ and CD8+ T cells. The results demonstrated that L2 domain of ErbB2 receptor is an immunodominant molecule. The mL2 domain of ErbB2 can induce an enhanced maturation and functional capacity of DC. It may become an effective strategy to induce anti-ErbB2 response.
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Xie Z, Harris-White ME, Wals PA, Frautschy SA, Finch CE, Morgan TE. Apolipoprotein J (clusterin) activates rodent microglia in vivo and in vitro. J Neurochem 2005; 93:1038-46. [PMID: 15857407 DOI: 10.1111/j.1471-4159.2005.03065.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Apolipoprotein J (apoJ; also known as clusterin and sulfated glycoprotein (SGP)-2) is associated with senile plaques in degenerating regions of Alzheimer's disease brains, where activated microglia are also prominent. We show a functional link between apoJ and activated microglia by demonstrating that exogenous apoJ activates rodent microglia in vivo and in vitro. Intracerebroventricular infusion of purified human plasma apoJ ( approximately 4 microg over 28 days) activated parenchymal microglia to a phenotype characterized by enlarged cell bodies and processes (phosphotyrosine immunostaining). In vitro, primary rat microglia were also activated by apoJ, with changes in morphology and induction of major histocompatibility complex class II (MHCII) antigen. ApoJ increased the secretion of reactive nitrogen intermediates in a dose-dependent manner (EC(50) 112 nm), which was completely blocked by aminoguanidine (AG), a nitric oxide synthase inhibitor. However, AG did not block the increased secretion of tumor necrosis factor-alpha by apoJ (EC(50) 55 nm). Microglial activation by apoJ was also blocked by an anti-apoJ monoclonal antibody (G7), and by chemical cleavage of apoJ with 2-nitro-5-thiocyanobenzoate. The mitogen-activated protein kinase kinase and protein kinase C inhibitors PD98059 and H7 inhibited apoJ-mediated induction of reactive nitrogen intermediate secretion from cultured microglia. As a functional measure, apoJ-activated microglia secreted neurotoxic agents in a microglia-neuron co-culture model. We hypothesize that ApoJ contributes to chronic inflammation and neurotoxicity through direct effects on microglia.
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225
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Jin M, Wang XM, Tu Y, Zhang XH, Gao X, Guo N, Xie Z, Zhao G, Jing N, Li BM, Yu L. The negative cell cycle regulator, Tob (transducer of ErbB-2), is a multifunctional protein involved in hippocampus-dependent learning and memory. Neuroscience 2005; 131:647-59. [PMID: 15730870 DOI: 10.1016/j.neuroscience.2004.10.044] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/03/2004] [Indexed: 10/25/2022]
Abstract
Tob (transducer of ErbB2) is a negative cell cycle regulator with anti-proliferative activity in the periphery. Using a behavioral screening paradigm to look for novel gene functions in the brain, we identified Tob as a brain-expressed protein involved in learning and memory. Behavioral training of fear-conditioning triggered a transient elevation of Tob protein, which preceded the formation of long-term memory. Functional perturbation of Tob by intra-CA1 infusion of antisense oligonucleotides in rats impaired spatial learning and memory in the Morris water maze and long-term memory for contextual fear conditioning, two behavioral paradigms that require the hippocampus. Furthermore, long-term potentiation was suppressed by Tob antisense infusion into the CA1 region. Together, these results indicate that the negative cell cycle regulator Tob is a multifunctional protein involved in hippocampus-dependent learning and memory.
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MESH Headings
- Amino Acid Sequence
- Animals
- Animals, Newborn
- Avoidance Learning/physiology
- Base Sequence
- Behavior, Animal/drug effects
- Behavior, Animal/physiology
- Blotting, Northern/methods
- Blotting, Western/methods
- Carrier Proteins/physiology
- Cloning, Molecular
- Conditioning, Classical/physiology
- Excitatory Postsynaptic Potentials/drug effects
- Excitatory Postsynaptic Potentials/radiation effects
- Fear
- Gene Expression/physiology
- Gene Expression Regulation/physiology
- Gene Library
- Hippocampus/metabolism
- Humans
- Intracellular Signaling Peptides and Proteins
- Long-Term Potentiation/drug effects
- Long-Term Potentiation/physiology
- Long-Term Potentiation/radiation effects
- Male
- Maze Learning
- Mice
- Mice, Inbred BALB C
- Mice, Inbred ICR
- Oligonucleotides/pharmacology
- Oligonucleotides, Antisense/pharmacology
- Rats
- Rats, Sprague-Dawley
- Reaction Time/drug effects
- Reaction Time/physiology
- Time Factors
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